title: Analysis of a soluble (UreD:UreF:UreG)2 accessory protein complex and its interactions with Klebsiella aerogenes urease by mass spectrometry.
abstract: Maturation of the nickel-containing urease of Klebsiella aerogenes is facilitated by the UreD, UreF, and UreG accessory proteins along with the UreE metallo-chaperone. A fusion of the maltose binding protein and UreD (MBP-UreD) was co-isolated with UreF and UreG in a soluble complex possessing a (MBPUreD: UreF:UreG)2 quaternary structure. Within this complex a UreF:UreF interaction was identified by chemical cross-linking of the amino termini of its two UreF protomers, as shown by mass spectrometry of tryptic peptides. A preactivation complex was formed by the interaction of (MBP-UreD:UreF:UreG)2 and urease. Mass spectrometry of intact protein species revealed a pathway for synthesis of the urease pre-activation complex in which individual hetero-trimer units of the (MBP-UreD:UreF:UreG)2 complex bind to urease. Together, these data provide important new insights into the structures of protein complexes associated with urease activation.
authors.affiliation: Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Farrugia
authors.forename: Linjie
authors.initials: L
authors.lastname: Han
authors.forename: Yueyang
authors.initials: Y
authors.lastname: Zhong
authors.forename: Jodi L
authors.initials: JL
authors.lastname: Boer
authors.forename: Brandon T
authors.initials: BT
authors.lastname: Ruotolo
authors.forename: Robert P
authors.initials: RP
authors.lastname: Hausinger
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism*; D002352:Carrier Proteins / Q000737:chemistry / Q000378:metabolism*; D021902:Enterobacter aerogenes / Q000737:chemistry / Q000201:enzymology* / Q000378:metabolism; D004789:Enzyme Activation; D008958:Models, Molecular; D028044:Phosphate-Binding Proteins; D060066:Protein Interaction Maps; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D014510:Urease / Q000737:chemistry / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D002352:Carrier Proteins; D028044:Phosphate-Binding Proteins; C086767:UreD protein, Bacteria; C101639:UreF protein, bacteria; C082270:ureG protein, Bacteria; D014510:Urease